Seat position and the risk of serious thoracoabdominal injury in lateral motor vehicle crashes

CONTEXT: Previous studies have suggested that motor vehicle occupants seated on the near-side of a lateral impact have a higher proportion of thoracoabdominal injuries. However, due to limitations in previous studies, the true association between seat position, side of lateral impact, and thoracoabdominal injury is unclear. OBJECTIVE: To assess the relationship between seat position (i.e., near-side, middle-seat, and far-side, regardless of row), side of lateral motor vehicle crash (MVC), and serious thoracoabdominal injury after adjusting for important crash factors. DESIGN: National population-based cohort of adult subjects involved in MVCs and included in the National Automotive Sampling System Crashworthiness Data System database (NASS CDS) from 1995 to 2003. PATIENTS: Occupants aged > or =16 years involved in MVCs where the highest external deformation of the vehicle was located on the right or left side (i.e., lateral). MAIN OUTCOME MEASURE: Serious thoracic or abdominal injury, defined as an Abbreviated Injury Scale (AIS) > or =3 in the thoracic or abdominal body region. RESULTS: Fifteen thousand, one hundred and sixty persons involved in primary lateral MVCs were represented in the NASS CDS database during the 9-year period. There were 1867 (2%) persons with serious thoracic injuries and 507 persons (0.5%) with serious abdominal injuries. In multivariable logistic regression models that adjusted for important crash factors and the NASS CDS sampling design, seat position was a strong effect modifier of the association between side of lateral impact and serious thoracic (p<0.0001) and abdominal (p=0.0009) injury, with the risk of serious thoracic and abdominal injury highest for occupants seated on the near-side of the crash. The mean probability of injury was higher for near-side and middle-seat occupants compared to far-side occupants, and the probability of thoracic injury was approximately four times higher than that of abdominal injury for all seat positions. CONCLUSIONS: There is a strong, synergistic relationship between seat position and side of lateral MVC in assessing risk of serious thoracic and abdominal injury among adult occupants. The probability of serious thoracoabdominal injury increases with increasing proximity of seat position to side of the crash and the risk of thoracic injury is higher than abdominal injury for all seat positions.     

Patterns and trends in injuries due to chemicals based on OSHA occupational injury and illness statistics

The Occupational Safety and Health Administration (OSHA) and the Bureau of Labor Statistics (BLS) provide the Survey of Occupational Illness and Injury (SOII) statistics from 1992 to 2006, which is often used to measure the rate of injuries and illness in industry. The present system of gathering and classifying this data was implemented in 1992 with minor changes in 2002. It is hoped that using these statistics to measure safety progress and determine patterns of injury will guide further improvements in chemical safety. Recognizing such factors as what chemicals most frequently cause injury can help to focus safety efforts regarding that chemical. Factors such as what part of the body is most commonly affected by particular chemicals can lead to improved personnel protection practices. This paper provides a detailed analysis of injuries due to chemicals using OSHA's SOII data, which offers valuable insight into measures that should be taken to reduce injuries due to chemicals.     

Crash costs in the United States by crash geometry

MAIN OBJECTIVES: This study was conducted to estimate the costs per crash for three police-coded crash severity groupings within 16 selected crash geometry types and within two speed limit categories (or=50 mph). METHODS: We merged previously developed costs per victim by abbreviated injury scale (AIS) score into U.S. crash data files that scored injuries in both the AIS and police-coded severity scales to estimate injury costs, then aggregated the estimates into costs per crash by maximum injury severity. RESULTS: The most costly crashes were non-intersection fatal/disabling injury crashes on a road with a speed limit of 50 miles per hour or higher where multiple vehicles crashed head-on or a single vehicle struck a human (over 1.69 US dollars and 1.16 million US dollars per crash, respectively). The annual cost of police-reported run-off-road collisions, which include both rollovers and object impacts, represented 34% of total costs. CONCLUSIONS: This paper provides cost estimates useful for evaluating roadway countermeasures and for designing vehicles to minimize crash harm. It gives unit costs of crashes by type in the coding system used by the police. The costs are in an appropriate form for economic analysis of countermeasures addressing locally defined problems identified by analyzing police crash reports.     

Costs of occupational injuries in construction in the United States

This paper presents costs of fatal and nonfatal injuries for the construction industry using 2002 national incidence data from the Bureau of Labor Statistics and a comprehensive cost model that includes direct medical costs, indirect losses in wage and household productivity, as well as an estimate of the quality of life costs due to injury. Costs are presented at the three-digit industry level, by worker characteristics, and by detailed source and event of injury. The total costs of fatal and nonfatal injuries in the construction industry were estimated at $11.5 billion in 2002, 15% of the costs for all private industry. The average cost per case of fatal or nonfatal injury is $27,000 in construction, almost double the per-case cost of $15,000 for all industry in 2002. Five industries accounted for over half the industry's total fatal and nonfatal injury costs. They were miscellaneous special trade contractors (SIC 179), followed by plumbing, heating and air-conditioning (SIC 171), electrical work (SIC 173), heavy construction except highway (SIC 162), and residential building construction (SIC 152), each with over $1 billion in costs.     

A spatial generalized ordered response model to examine highway crash injury severity

This paper proposes a flexible econometric structure for injury severity analysis at the level of individual crashes that recognizes the ordinal nature of injury severity categories, allows unobserved heterogeneity in the effects of contributing factors, as well as accommodates spatial dependencies in the injury severity levels experienced in crashes that occur close to one another in space. The modeling framework is applied to analyze the injury severity sustained in crashes occurring on highway road segments in Austin, Texas. The sample is drawn from the Texas Department of Transportation (TxDOT) crash incident files from 2009 and includes a variety of crash characteristics, highway design attributes, driver and vehicle characteristics, and environmental factors. The results from our analysis underscore the value of our proposed model for data fit purposes as well as to accurately estimate variable effects. The most important determinants of injury severity on highways, according to our results, are (1) whether any vehicle occupant is ejected, (2) whether collision type is head-on, (3) whether any vehicle involved in the crash overturned, (4) whether any vehicle occupant is unrestrained by a seat-belt, and (5) whether a commercial truck is involved.     

Safety climate and self-reported injury: assessing the mediating role of employee safety control

To further reduce injuries in the workplace, companies have begun focusing on organizational factors which may contribute to workplace safety. Safety climate is an organizational factor commonly cited as a predictor of injury occurrence. Characterized by the shared perceptions of employees, safety climate can be viewed as a snapshot of the prevailing state of safety in the organization at a discrete point in time. However, few studies have elaborated plausible mechanisms through which safety climate likely influences injury occurrence. A mediating model is proposed to link safety climate (i.e., management commitment to safety, return-to-work policies, post-injury administration, and safety training) with self-reported injury through employees' perceived control on safety. Factorial evidence substantiated that management commitment to safety, return-to-work policies, post-injury administration, and safety training are important dimensions of safety climate. In addition, the data support that safety climate is a critical factor predicting the history of a self-reported occupational injury, and that employee safety control mediates the relationship between safety climate and occupational injury. These findings highlight the importance of incorporating organizational factors and workers' characteristics in efforts to improve organizational safety performance.     

Headrest position during normal driving: Implication to neck injury risk in rear crashes

The gap and relative height of headrest behind drivers were determined for 1915 vehicles approaching an intersection on a two lane road. Vehicle type and headrest adjustment were also evaluated using film of normal driving taken by the Insurance Institute for Highway Safety. Only 10% of drivers had headrests in the most favorable position to prevent neck extension during a rearend crash. 73% of cars had adjustable headrests, but only a quarter were placed in the up position. 83% of the adjustable headrests could have been raised to better protect the driver. Hyge sled tests were run to determine biomechanical responses for the various conditions observed in normal driving. This included three headrest heights and three gaps behind the head. Neck extension from the Hybrid III dummy was normalized to the response for a high, close headrest, and injury risk was assumed to be proportional to neck extension. The current driving situation has a relative injury risk of 3.4 in rearend crashes, compared to 1.0 for the favorable condition. If all adjustable headrests were placed in the up position, the relative risk would be lowered to 2.4, a 28.3% reduction in whiplash injury risk. Public education and vehicle design should address the importance of proper headrest placement for driving safety.     

Formulating a programme of repairs to structural home injury hazards in New Zealand

Home injuries are a substantial health burden worldwide, with the home setting being at least as important as the road for injury. Focusing on common injury hazards presented by the home environment, we sought to examine the justification for significant expenditure on safety-related repairs to the housing stock. Trained inspectors assessed 961 New Zealand houses for injury hazards. Using administrative data from the Accident Compensation Corporation (the national injury insurance agency), 1328 home injuries were identified amongst the 1612 occupants of these houses over the 2006–2009 period. Telephone interviews gathered data on the location and nature of these injuries, and the attitudes of those injured to potential injury hazards in their homes. Commonly occurring injury hazards that could be repaired at modest cost were identified based on their prevalence estimated by the housing inspection, and their location with respect to the areas of the home where the injuries occurred (identified during the telephone interviews). About 38% of the home injuries studied were potentially related to a structural aspect of the home environment. Common safety hazards included the lack of working smoke detectors (65% of the sample), inadequately fenced driveways (55%), hot water temperatures measured at over 60° (49%) and poorly lit access to the house (34%). A protocol for identifying and repairing important common hazards was designed. The actual safety effects of this protocol are in the process of being examined in a randomised controlled trial.     

Estimating the human recovery costs of seriously injured road crash casualties

Road crashes result in substantial trauma and costs to societies around the world. Robust costing methods are an important tool to estimate costs associated with road trauma, and are key inputs into policy development and cost–benefit analysis for road safety programmes and infrastructure projects. With an expanding focus on seriously injured road crash casualties, in addition to the long standing focus on fatalities, methods for costing seriously injured casualties are becoming increasingly important. Some road safety agencies are defining a seriously injured casualty as an individual that was admitted to hospital following a road crash, and as a result, hospital separation data provide substantial potential for estimating the costs associated with seriously injured road crash casualties. The aim of this study is to establish techniques for estimating the human recovery costs of (non-fatal) seriously injured road crash casualties directly from hospital separation data. An individuals’ road crash-related hospitalisation record and their personal injury insurance claim were linked for road crashes that occurred in New South Wales, Australia. These records provided the means for estimating all of the costs to the casualty directly related to their recovery from their injuries. A total of 10,897 seriously injured road crash casualties were identified and four methods for estimating their recovery costs were examined, using either unit record or aggregated hospital separation data. The methods are shown to provide robust techniques for estimating the human recovery costs of seriously injured road crash casualties, that may prove useful for identifying, implementing and evaluating safety programmes intended to reduce the incidence of road crash-related serious injuries.     

Work-related ladder fall fractures: identification and diagnosis validation using narrative text

OBJECTIVE: To identify ladder-related fracture injuries and determine how ladder fall fractures differ from other ladder-related injuries. METHODS: Ladder-related fracture cases were identified using narrative text and coded data from workers' compensation claims. Potential cases were identified by text searches and verified with claim records. Injury characteristics were compared using proportionate injury ratios. RESULTS: Of 9826 ladder-related injuries, 7% resulted in fracture cases. Falls caused 89% of fractures and resulted in more medical costs and disability days than other injuries. Frequent mechanisms were ladder instability (22%) and lost footing (22%). Narrative text searches identified 17% more fractures than injury codes alone. Males were more likely to sustain a fall fracture than other injuries; construction workers were most likely, and retail workers were the least likely to sustain fractures. CONCLUSIONS: Fractures are an important injury from ladder falls, resulting more serious consequences than other ladder-related injuries. Text analysis can improve the quality and utility of workers compensation data by identifying and understanding injury causes. Proportionate injury ratios are also useful for making cross-group comparisons of injury experience when denominator data are not available. Greater attention to risk factors for ladder falls is needed for targeting interventions.     

Freeway speed limits and traffic fatalities in Washington State.

BACKGROUND: In 1987 individual states in the USA were allowed to raise speed limits on rural freeways from 55 to 65 mph. Analyses of the impact of the increased speed limits on highway safety have produced conflicting results. OBJECTIVE: To determine if the 1987 speed limit increase on Washington State's rural freeways affected the incidence of fatal crashes or all crashes on rural freeways, or affected average vehicle speeds or speed variance. DESIGN: An ecological study of crashes and vehicle speeds on Washington State freeways from 1974 through 1994. RESULTS: The incidence of fatal crashes more than doubled after 1987, compared with what would have been expected if there had been no speed limit increase, rate ratio 2.1 (95% confidence interval (CI), 1.6-2.7). This resulted in an excess of 26.4 deaths per year on rural freeways in Washington State. The total crash rate did not change substantially, rate ratio 1.1 (95% CI, 1.0-1.3). Average vehicle speed increased by 5.5 mph. Speed variance was not affected by the speed limit increase. CONCLUSIONS: The speed limit increase was associated with a higher fatal crash rate and more deaths on freeways in Washington State.     

The neck injury criterion: future considerations

The cost of whiplash injuries--both in dollars spent for medical care and disability, and in terms of human suffering--are quite high in westernized nations. This is of particular interest both from a public health perspective and a general societal one because the disorder is theoretically preventable: in the very least it can be minimized. This can be achieved with crash prevention strategies and improvements in vehicle safety design--especially with more effective seat back and head restraint systems. Toward the goal of developing a gold standard for safety research in this area, a neck injury criterion (NIC) was proposed by Bostr?m et al. in 1996 (Bostr?m O., Svennson, M.Y., Aldman, B. et al., 1996. In: Proceedings of the International Conference on the Biomechanics of Impact, Dublin, Ireland). This criterion considers the relative horizontal acceleration and velocity between the bottom (T1) and top (C1) of the cervical spine and has face validity based on current literature. However, the NIC has still not been subjected to rigorous scientific investigation or validation in terms of its representativeness of human occupant injury. Such investigation should specifically consider, first, whether the NIC provides an adequate proxy for all potential neck injuries due to whiplash and, secondly, whether the proposed threshold value of 15 m2/s2 is an appropriate level for the stated goal. Based on a review of recent literature, recent human volunteer crash tests by Wheeler et al. and the those of the Spine Research Institute of San Diego, and based on mathematical MADYMO analysis of the first real world crash pulse data, it appears that the threshold for acute injury in the general population is likely to require a lowering of the originally proposed NIC value, and additional parameters, such as considering a forward rebound phase or neck extension criteria may be necessary. The conclusions of this paper should be considered preliminary because the numbers of crash test subjects and real world injury victims does not allow for rigorous statistical analysis. Certainly, ongoing work will be necessary to investigate this further and larger scale analysis of more onboard crash data will prove invaluable.     

Total costs of bicycle injuries in Norway: correcting injury figures and indicating data needs

Bicycle injuries and fatalities are reported by the police to Statistics Norway. Fatality records from the police are then corrected with Vital Statistics records. However, there is no complete hospital recording that could provide more correct data for bicycle injuries. Bicycle injuries are underreported in official data. There is a nearly complete omission of single bicycle accidents. This disguises societal accident costs and curtails the identification of black spots and effective infrastructure improvements.

This paper provides an estimate of total bicycle injuries in Norway and the total costs of these injuries. Application of case study hospital data from Norwegian towns enabled an estimation of the relationship between these data and the official data, including the distribution of injuries by severity. Costs were then assessed by applying official monetary values for given levels of injury severity.

Total annual bicycle injury costs are huge, but these costs must be balanced against the benefits of bicycling, related to health and environment. Accident reporting and data should be enhanced to enable a reduction of bicycle injuries.     

How intoxicated are drivers in the United States? Estimating the extent, risks and costs per kilometer of driving by blood alcohol level.

This study develops and applies an algorithm with international applicability for estimating vehicle kilometers (kms) driven by blood alcohol level (BAL) from police crash report data. In the United States, an estimated one in 120 kms was driven with BAL > or = 0.10% in 1992-1993. The ratio increased to 1 in 7 kms driven on weekend evenings. The estimated cost per vehicle km driven with BAL > or = 0.08% was $3.40 compared to $0.07 per sober km. Males, those age 21-29 and those driving between 22:00 and 04:00 had the greatest percentage of driving with BAL > or = 0.08%. These estimates are computed, in part, from early 1960s data on crash odds by driver BAL and assume crash odds by BAL relative to sober do not vary with driver age and sex. Preliminary investigation indicates that the method provides reliable estimates of alcohol-positive kms from roadside surveys at night, but seems to over-estimate high-BAL kms. Direct field validation is highly desirable.     

Suicidal ideation, antidepressive medication and car crash injury

OBJECTIVE: This study aimed to investigate the association between suicidal ideation, antidepressive medication and the risk of a car crash resulting in serious injury. DESIGN: This was a population-based case-control study. Cases were car drivers who were involved in crashes in which at least one occupant of their car was hospitalised or killed. Controls were selected using a cluster random sample of car drivers on the roads in the same region. Self-reported information on suicidal ideation in the 12 months prior to the crash or roadside survey, current usage of antidepressive medication as well as other crash-related risk factors was obtained from the drivers, or by proxy, using an interviewer-administered questionnaire. SETTING: The study was conducted in the Auckland region of New Zealand in 1998 and 1999. RESULTS: There was a significant association between drivers who had suicidal ideation but without current antidepressive medication and the risk of an injury crash (OR=4.16, 95% CI=2.14-8.10), when compared to drivers without any suicidal ideation. CONCLUSION: The risk of an injury crash was significantly increased for those drivers who reported to have previous or current suicidal ideation but without current antidepressant medication.     

Environmental factors associated with crash-related mortality and injury among taxi drivers in New South Wales, Australia

This exploratory study aims to investigate the associations between some environmental factors and the increased risk of motor vehicle crash-related injuries among taxi drivers. Information utilised in the study are obtained from police reports of all road traffic accidents that occurred on the roads between 1996 and 2000 in New South Wales (NSW), Australia. Of the 7923 taxi drivers who involved in crashes, nearly 10% (n = 750) were killed or injured. Results indicate sex, and two environmental factors are significantly associated with an increased risk of crash-related mortality and injury among taxi drivers. The adjusted relative risk of crash-related mortality and injury is increased by 60% for those who work the night shift (OR = 1.59, 95%CI = 1.35-1.88), and by 20% for those who do not carry any passenger on board (OR = 1.20, 95%CI = 1.02-1.41) should these drivers involve in a crash. The increased relative risk of crash-related mortality and injury is nearly 2.5 times for female taxi drivers (OR = 2.30, 95%CI = 1.45-3.65) when compared with their male counterparts.     

Effects of osteoporosis on AIS 3+ injury risk in motor-vehicle crashes

Older occupants in motor-vehicle crashes are more likely to experience injury than younger occupants. One possible reason for this is that increasing age is associated with increased prevalence of osteoporosis, which decreases bone strength.Crash-injury data were used with Bayes’ Theorem to estimate the conditional probability of AIS 3+ skeletal injury given that an occupant is osteoporotic for the injury to the head, spine, thorax, lower extremities, and upper extremities. This requires the conditional probabilities of osteoporosis given AIS 3+ injury for each of the body regions, which were determined from analysis of the Crash Injury Research and Engineering Network database. It also requires information on probability of osteoporosis in the crash-involved population and the probabilities of AIS 3+ skeletal injury to different body regions in crashes. The latter probabilities were obtained from the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) database. The former was obtained by modeling the probability of osteoporosis in the US populations using data from the 2006 National Health Examination Nutrition Survey and applying this model to the estimate of the crash-involved population in NASS-CDS. To attempt to account for the effects of age on injury outcome that are independent of osteoporosis, only data from occupants who were 60 years of age or older were used in all analyses.Results indicate that the only body region that experiences a statistically significant change in fracture injury risk with osteoporosis is the spine, for which osteoporosis increases the risk of AIS 3+ fracture by 3.28 times, or from 0.41% to 1.34% (p < 0.0001). This finding suggests that the increase in AIS 3+ injury risk with age for non-spine injuries is likely influenced by factors other than osteoporosis.     

Estimation of the social costs of home injury: a comparison with estimates for road injury

Home injury is thought to constitute a major health burden in most developed countries. However, efforts to address this burden have been hampered by reluctance from outside agencies to interfere with the home environment of individuals, even if it benefits the occupant's safety. This paper outlines cost–benefit evaluation methods established in the transport safety domain applied to home safety to estimate the social cost of unintentional home injury in New Zealand. Estimates of costs imposed on society by home injury can provide an important motivator for initiating research and programmes to reduce home injury risk. Data sources used included mortality data, hospitalisation data and data on minor injuries that required medical treatment, but not hospital admission. We estimated that unintentional home injuries in New Zealand impose an annual social cost of about $NZ 13 billion (about $US 9 billion), which is about 3.5 times the annual social cost of road injury. These estimates provide a rational evidence base for decisions on housing-focused safety regulation or interventions that always carry some cost, and therefore need to be weighed against the benefits of injuries potentially prevented.     

Firearm storage practices and rates of unintentional firearm deaths in the United States

BACKGROUND: The American Academy of Pediatrics and the American Medical Association recommend storing firearms unloaded and locked up to minimize the chance of injury. Although these recommendations appeal to common sense, no study has yet addressed whether firearm storage practices influence the risk of unintentional firearm injury. METHODS: Negative binomial regression analyses were used to assess the cross sectional relation between firearm storage practices and rates of unintentional firearm death in the United States, controlling for rates of firearm prevalence, poverty and urbanization. Recently available state-level measures of household firearm prevalence and firearm storage practices were obtained from the 2002 Behavioral Risk Factor Surveillance System. Unintentional firearm death counts and population data came from the National Center for Health Statistics. RESULTS: Independent of firearm prevalence, urbanization, and poverty, a disproportionately large share of unintentional firearm fatalities occurred in states where gun owners were more likely to store their firearms loaded, the greatest risk occurring in states where loaded firearms were more likely to be stored unlocked. CONCLUSION: Our findings provide empirical support for recommendations issued by the AMA and the AAP that firearms should be stored unloaded and locked, and suggest that promoting safer storage practices could save many lives.     

Industrial and occupational ergonomics in the petrochemical process industry: a regression trees approach

This work is an attempt to apply classification tree methods to data regarding accidents in a medium-sized refinery, so as to identify the important relationships between the variables, which can be considered as decision-making rules when adopting any measures for improvement. The results obtained using the CART (Classification And Regression Trees) method proved to be the most precise and, in general, they are encouraging concerning the use of tree diagrams as preliminary explorative techniques for the assessment of the ergonomic, management and operational parameters which influence high accident risk situations. The Occupational Injury analysis carried out in this paper was planned as a dynamic process and can be repeated systematically. The CART technique, which considers a very wide set of objective and predictive variables, shows new cause-effect correlations in occupational safety which had never been previously described, highlighting possible injury risk groups and supporting decision-making in these areas. The use of classification trees must not, however, be seen as an attempt to supplant other techniques, but as a complementary method which can be integrated into traditional types of analysis.